feat(python): drop Python 3.5 compatibility (fixes #810)

python/setup.py

@@ -59,7 +59,7 @@ setup(
     entry_points={"console_scripts": ["trezorctl=trezorlib.cli.trezorctl:cli"]},
     install_requires=install_requires,
     extras_require=extras_require,
-    python_requires=">=3.5",
+    python_requires=">=3.6",
     include_package_data=True,
     zip_safe=False,
     classifiers=[

python/tox.ini

@@ -1,9 +1,9 @@
 [tox]
 envlist =
-#    py35,  XXX revisit, see also https://github.com/trezor/trezor-firmware/issues/810
     py36,
     py37,
     py38,
+    py39,
 
 [testenv]
 deps =